Six-Steps Process of Structural Assessment of Heritage Timber Structures: Definition Based on the State of the Art

Each construction material deals with specific mechanical properties, their distribution, damage mechanisms, and degradation processes. Therefore, each material requires a particular assessment approach in order to derive a reliable description of the residual performance of the structure, correctly remove the cause of damage, and proceed with the correct design of interventions. The aims of this paper are, first, the definition of a process of assessment and retrofitting of existing timber structures, both for engineered and heritage/traditional timber structures, and second, a comparison between the defined assessment process and its contents, and the content of existing guidelines, codes, and standards. In order to gain a definition of the process of assessment and retrofitting of existing timber structures, the content of scientific papers and articles was analyzed, and on this basis, an assessment process with six main steps and three milestones was developed. The content of the guidelines, codes and standards was afterwards analyzed basing on this six-steps assessment process. From a comparison among the current literature, guidelines, codes, and standards, interesting results emerged that gave us a picture of the European knowledge and interests on the assessment of existing timber structures. Not only agreement, but also discrepancies, variances, and incongruities were identified as possible topics for future researc

Set-valued Hermite interpolation

AbstractThe problem of interpolating a set-valued function with convex images is addressed by means of directed sets. A directed set will be visualised as a usually non-convex set in Rn consisting of three parts together with its normal directions: the convex, the concave and the mixed-type part. In the Banach space of the directed sets, a mapping resembling the Kergin map is established. The interpolating property and error estimates similar to the point-wise case are then shown; the representation of the interpolant through means of divided differences is given. A comparison to other set-valued approaches is presented. The method developed within the article is extended to the scope of the Hermite interpolation by using the derivative notion in the Banach space of directed sets. Finally, a numerical analysis of the explained technique corroborates the theoretical results

Ricerca e sperimentazione fra arte e medium. Intervista a Giuliano Giuman

Exsperimentation and intermediality: these are the main factors which, in the last fifthy years, have marked the complex aesthetic research of Giuliano Giuman. Starting from painting debuts until the most recent glass works, this master artist from Perugia describes himself in an interview full of elements that explore the origin of his unique artistic language characterised by a continuous evolution.Sperimentazione e intermedialità: sono questi i principali fattori che, negli ultimi cinquant’anni, hanno segnato la complessa ricerca estetica di Giuliano Giuman. Partendo dagli esordi pittorici fino alle più recenti opere in vetro, il maestro perugino si racconta in un’intervista ricca di elementi che approfondiscono l’origine del suo personale linguaggio artistico destinato a una continua evoluzione

Charakterisierung des geraden Blattes mit schrägem Stoß und des schrägen Hakenblattes mit schrägem Stoß und Keil (Jupitergelenk)

Historical timber frame structures constitute a huge part of the cultural heritage. The preservation of such structures requires a good understanding of both the original constructional methods and of the load-bearing principles of the structure. Carpentry connections are crucial for the behaviour of the structures, and a good understanding of them is of basic importance to lead a correct structural analysis. The present work introduces the basic load-bearing principles of the stop-splayed and tabled scarf joint with key (Jupiter joint) and the halved undersquinted joint; two among the basic types of lengthening joints used in traditional half-timbered and frame structures. The halved joint was used as a reference for developing an overview on the general structural behaviour. Therefore, the problem was examined in depth with the experimental and numerical analysis of the halved undersquinted scarf. Basic analytical linear-elastic models were developed. Tests were conducted under static loads in order to describe the maximum load, failure mechanisms, position of the forces along the loading process, rotational stiffness, friction mechanisms and the influence of the geometry on the load-bearing behaviour. The analytical model, based on the initial assumptions was calibrated on the experimental results. The influence and function of both the sloped surfaces and the wedge is investigated through some intermediate geometries. Finally, in order to give general remarks about the behaviour of the splayed and tabled scarf with key joint (Jupiter joint) along the strong and weak axis, a small series of specimens were tested, in order to describe the interaction between normal force (N) and bending moment (M) in a N-M interaction diagram and to record the failure modes along the strong and weak axis. The experimental outputs were compared with the numerical results obtained from the structural analysis of the dome of Santiago de Cuba’s cathedral to verify the reliability of the analytical model and the experimental results. The case study was chosen because the inner timber framed structure of the building demonstrated reliability against earthquakes and hurricane along the centuries. Here, the Jupiter joint was employed in the dome’s structure. The description of such carpentry connections through a static model is of importance for the structural analysis of old timber structures with the aim of restoration and reinforcement of them.Historische Holzrahmen- und Fachwerkkonstruktionen bilden einen großen Teil des kulturellen Erbes. Die Erhaltung solcher Strukturen erfordert ein gutes Verständnis sowohl der ursprünglichen Konstruktionsmethoden als auch der tragenden Prinzipien der Strukturen. Zimmermannmäßige Verbindungen sind entscheidend für das Verhalten der Strukturen, und ein gutes Verständnis dieser ist von grundlegender Bedeutung, um eine korrekte strukturelle Analyse zu führen. Diese Arbeit beschäftigt sich mit den grundlegenden Tragprinzipien des Jupitergelenks (schräges Hakenblatt mit schrägem Stoß und Keil) und des geraden Blattes mit schrägem Stoß. Diese beiden zimmermannsmäßigen Verbindungen wurden in traditionellen Fachwerk- und hölzernen Rahmenstrukturen eingesetzt. Die bis dato nicht systematisch untersuchten Tragmechanismen wurden in der Tiefe mit experimenteller und numerischer Analyse des geraden Blattes mit schrägem Stoß eruiert. Es wurden dabei grundlegende analytische linear-elastische Modelle entwickelt. Die experimentellen Untersuchungen wurden unter verschiedenen statischen Laststellungen durchgeführt, um die Tragfähigkeit, die Versagensmechanismen, die Rotationssteifigkeit, die Reibungsmechanismen und den Einfluss der Geometrie auf das Lastführungsverhalten zu beschreiben. Es erfolgte eine allgemeine Beschreibung zum Verhalten des schrägen Hakenblattes mit schrägem Stoß und Keil (Jupitergelenk) in Bezug auf die beiden Hauptachsen des Bauteilquerschnitts. Hierbei wurden Parameterstudien zur Beziehung und Wechselwirkung zwischen Normalkraft (N) und Biegemoment (M) durchgeführt und im Ergebnis in N-M Interaktionsdiagrammen dargestellt. Die experimentellen Ergebnisse wurden mit den numerischen Ergebnissen der strukturellen Analyse der Kuppel der Kathedrale Santiago de Cuba verglichen, um die Zuverlässigkeit des analytischen Modells zu überprüfen. Die Fallstudie wurde gewählt, weil die innere Stabwerkkonstruktion des Gebäudes und der Kuppel im Laufe der Jahrhunderte widerstandsfähig gegen Erdbeben und Hurrikan blieb. Hier wurde das Jupitergelenk in der Struktur der Kuppel eingesetzt. Die Beschreibung solcher zimmermannmäßigen Verbindungen durch ein statisches Modell ist für die Tragwerksanalyse von alten Holzstrukturen mit dem Ziel ihrer Wiederherstellung und Verstärkung bedeutend

Dinamica al suolo di velivoli con freni differenziali: modellazione, progetto controllori e studio di leggi di guida con miscelazione dei comandi

Il seguente lavoro di tesi indaga e analizza il comportamento di un velivolo nelle fasi d'atterraggio dall'impatto al suolo fino al suo completo arresto. Gli obiettivi sono stati principalmente due: la progettazione di leggi di controllo direzionale attraverso l'intervento combinato su rudder, ruotino sterzante e freni differenziali; lo sviluppo di leggi di guida attraverso l'azione combinata di tali dispositivi in modo da ottimizzare la frenata. Per fare questo si è implementato in ambiente Matlab-Simulink il modello non-lineare del velivolo completo al suolo, il modello non-lineare del sistema frenante, il modello non-lineare degli ammortizzatori. Sono state eseguite simulazioni in presenza di raffica laterale e con intervento sui singoli controlli per verificarne le caratteristiche prestazionali ed in modo da definire dei criteri logici su cui basare la determinazione delle leggi di guida

TIMBER STRUCTURAL TECHNIQUES FROM THE DAWN OF THE CIVILIZATION TO THE EXPANSION OF CITIES IN THE XIX CENTURY IN EUROPE AND ITS COLONIES

This paper is a general description of the state-of-the-art on the European and colonial building techniques found in wooden buildings that currently exist. The description of the use and diffusion of the wooden structures is made by a brief explanation of the relative structural systems, as well as the peculiarities of the elements that compose it, its operating principles, the points of weakness and the joints used. Thus, the English and German techniques of structural timber frameworks are described in detail. On the other hand, other structural techniques and their evolution are presented through a review of works and documents that describe them accurately

Effetto dei suoli degradati sul comportamento vegeto-produttivo della vite

In Italian vineyards it is common to find more or less extended areas with chemico-physical or biological soil deficiencies and problems in plant vigor and grape production. A reduced agronomic functionality is caused by wrong soil managements and improper land preparation before vine plantations. A strong land transformation alters, in fact, the existing natural balance, causing loss of organic matter and nutrients, erosions, reduction of available water and metal accumulation. This phenomenon affects the growth of vines and the grape yields. The aim of this work is to evaluate the effect of degraded soils on the vineyards of two Tuscan vine-growing regions (Chianti Classico and Maremma Toscana). In two farms, we have identified respectively three degraded and three non-degraded areas in order to assess the fitness of the vines and the quality of the grapes. We found marked differences between degraded and non-degraded areas: as expected, the soil conditions have influenced the vigor of the plants, the production and the grapes had an unbalanced maturation